This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-281772, filed Sep. 18, 2000, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to an electronic apparatus such as a desktop personal computer, and more particularly, to the construction of a main body having therein function parts, such as a power unit and a system substrate mounted with a CPU.
2. Description of the Related Art
A desktop personal computer comprises a main body placed on a desk and a display device connected electrically to the main body. The main body includes a housing in the form of a rectangular box. Principal function parts, such as a system substrate mounted with a CPU, hard disk drive, CD-ROM drive, and power unit, are collectively held in the housing.
The housing includes a chassis and a top cover that spreads over the chassis. The chassis is a steel sheet formed by sheet metal stamping. The function parts including the system substrate and accessories are supported on the chassis. The top cover includes a top plate and left- and right-hand side plates, and is removably screwed to the chassis. In carrying out maintenance operation for the main body or expanding the functions of the system substrate, therefore, the top cover must be removed from the chassis so that the function parts supported on the chassis are exposed to the outside of the housing.
If the main body and the display device of the desktop personal computer are arranged side by side on the desk, the working space over the desk is narrowed. In many cases, therefore, the display device is placed on the top plate of the housing.
If the display device is left on the top plate of the housing, according to this arrangement for use, it hinders the top cover from being removed from the chassis. In carrying out a maintenance operation for the main body, for example, therefore, the display device must be moved from the position on the top plate to another place. If the display device is a CRT display device that is heavy and bulky, in particular, its movement takes much time and labor, and it is necessary to secure a wide space around the main body in which the CRT display device can be placed temporarily. Thus, preparations must be made before the maintenance of the main body is started, which slows down work.
Described in Jpn. Pat. Appln. KOKAI Publication No. 10-207575 is an arrangement that facilitates the maintenance of a control element, such as a system substrate, in a relatively large-scale computer system for business use. A housing according to this prior art includes outer and inner housings. The outer housing is designed so that it can support another housing on its top. The inner housing is supported so that it can be loaded into and unloaded from the outer housing. The inner housing contains the control element of the computer system therein. Thus, the control element can be exposed to the outside of the housing merely by drawing out the inner housing from the outer housing.
According to the prior art described above, the additional housing that is put on the housing having the control element built-in is a simple general-purpose cabinet of a drawer type. The general-purpose cabinet of this type is relatively light in weight, so that no substantial load acts on the outer housing that supports the cabinet from below. In other words, according to the aforesaid prior art, a heavy bulky article, such as the CRT display device, is not supposed to be placed on the housing. If the CRT display device is placed on the outer housing, therefore, the top face of the outer housing may possibly be deformed or warped downwards.
Thus, the position of the CRT display device may become unstable, or the deformation of the outer housing may prevent the inner housing from being drawn out smoothly.
According to the prior art described above, moreover, slide rails are attached to the inner surface of the outer housing and the outer surface of the inner housing, individually. The inner housing is slidable along the slide rails.
However, this arrangement requires use of dedicated slide rails for sliding the inner housing, and the number of indispensable parts increases correspondingly. Besides, the slide rails must be expressly attached to the inner and outer housings, which raises the manufacturing cost of the housing.
The present invention has been contrived in consideration of these circumstances, and its object is to provide an electronic apparatus designed so that function parts inside a cover can be exposed to the outside of a main body without moving a heavy bulky article, such as a display device, if any, off the cover, so that maintenance or expansion of the function parts can be carried out with ease.
In order to achieve the above object, an electronic apparatus according to a first aspect of the present invention comprises an external device and a main body having a plurality of function parts built-in. The main body includes a cover in the form of a hollow box, having a top plate on which the external device is placed, and a frame held inside the cover so as to be drawn out of the cover and supporting the function parts. The cover having strength such that the cover maintains the shape of a box even when the external device is placed on the top plate.
In order to achieve the above object, an electronic apparatus according to a second aspect of the invention comprises a main body having a plurality of function parts built-in, the main body including a cover in the form of a hollow box, having a bottom plate, a top plate on which an article is placed, and a pair of upright plates extending between the bottom plate and the top plate, and a frame held inside the cover so as to be drawn out of the cover and supporting the function parts. The cover has strength such that the cover maintains the shape of a box even when the article is placed on the top plate, and the frame is slidably supported by means of the bottom plate and the upright plates of the cover.
In order to achieve the above object, an electronic apparatus according to a third aspect of the invention comprises a main body having a plurality of function parts built-in, the main body including a cover in the form of a hollow box, having a top plate on which an article is placed and an opening at one end thereof, and a frame held inside the cover, being drawn out of the cover through the opening, and supporting the function parts, the cover having strength such that the cover maintains the shape of a box even when the article is placed on the top plate, and a latch device for holding the frame inside the cover, the latch device being adapted to be releasably caught by the cover when the frame is held inside the cover.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.